Several counters already have the need to use 64 atomic variables on 64 bit
platforms (see mm_counter_t in sched.h). We have to do ugly ifdefs to fall
back to 32 bit atomic on 32 bit platforms.
The VM statistics patch that I am working on will also make more extensive
use of atomic64.
This patch introduces a new type atomic_long_t by providing definitions in
asm-generic/atomic.h that works similar to the c "long" type. Its 32 bits
on 32 bit platforms and 64 bits on 64 bit platforms.
Also cleans up the determination of the mm_counter_t in sched.h.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Here is the patch to implement madvise(MADV_REMOVE) - which frees up a
given range of pages & its associated backing store. Current
implementation supports only shmfs/tmpfs and other filesystems return
-ENOSYS.
"Some app allocates large tmpfs files, then when some task quits and some
client disconnect, some memory can be released. However the only way to
release tmpfs-swap is to MADV_REMOVE". - Andrea Arcangeli
Databases want to use this feature to drop a section of their bufferpool
(shared memory segments) - without writing back to disk/swap space.
This feature is also useful for supporting hot-plug memory on UML.
Concerns raised by Andrew Morton:
- "We have no plan for holepunching! If we _do_ have such a plan (or
might in the future) then what would the API look like? I think
sys_holepunch(fd, start, len), so we should start out with that."
- Using madvise is very weird, because people will ask "why do I need to
mmap my file before I can stick a hole in it?"
- None of the other madvise operations call into the filesystem in this
manner. A broad question is: is this capability an MM operation or a
filesytem operation? truncate, for example, is a filesystem operation
which sometimes has MM side-effects. madvise is an mm operation and with
this patch, it gains FS side-effects, only they're really, really
significant ones."
Comments:
- Andrea suggested the fs operation too but then it's more efficient to
have it as a mm operation with fs side effects, because they don't
immediatly know fd and physical offset of the range. It's possible to
fixup in userland and to use the fs operation but it's more expensive,
the vmas are already in the kernel and we can use them.
Short term plan & Future Direction:
- We seem to need this interface only for shmfs/tmpfs files in the short
term. We have to add hooks into the filesystem for correctness and
completeness. This is what this patch does.
- In the future, plan is to support both fs and mmap apis also. This
also involves (other) filesystem specific functions to be implemented.
- Current patch doesn't support VM_NONLINEAR - which can be addressed in
the future.
Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Andrea Arcangeli <andrea@suse.de>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Ulrich Drepper <drepper@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
To allow multiple platforms to use the PXA27x OHCI driver, the platform
code needs to be moved into the board specific files in
arch/arm/mach-pxa. This patch does this for mainstone and adds
preliminary hooks to allow other boards to use the driver.
This has been compile tested for mainstone and successfully run on Spitz
(Sharp Zaurus SL-C3000) with the addition of an appropriate board
support file.
Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Nicolas Pitre <nico@cam.org>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Patch from Daniel Jacobowitz
Handle new EABI relocations when loading kernel modules. This is
necessary for CONFIG_AEABI kernels, and also for some broken
(since fixed) old ABI toolchains.
Signed-off-by: Daniel Jacobowitz <dan@codesourcery.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Hiroki Kaminaga
This patch defines a new macro: pfn_to_kaddr(pfn).
Same macro is already defined on other arch, such as i386.
Signed-off-by: Hiroki Kaminaga <kaminaga@sm.sony.co.jp>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Deepak Saxena
Mark the ioremap'd cookie/pointer in said functions as const since
we should not be actualy touching the data. This fixes a slew of
compile warnings on IXP4xx as our reads[bwl] already mark this
parameter as const.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
ARMv6K CPUs have SEV (send event) and WFE (wait for event) instructions
which allow the CPU clock to be suspended until another CPU issues a
SEV, rather than spinning on the lock wasting power. Make use of these
instructions.
Note that WFE does not wait if an event has been sent since the last WFE
cleared the event status, so although it may look racy, the instruction
implementation ensures that these are dealt with.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Lucas Correia Villa Real
This patch adds definitions to GPIO registers for the S3C2400 into
include/asm-arm/arch-s3c2410/regs-gpio.h.
Signed-off-by: Lucas Correia Villa Real <lucasvr@gobolinux.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Unfortunately, we have a symbol clash between the SA-1100 header and
some drivers. Since everywhere which needs SA1100 specifics includes
asm/hardware.h, we don't need to include it in the SA1100 io.h header.
In file included from drivers/net/wireless/wavelan_cs.p.h:459,
from drivers/net/wireless/wavelan_cs.c:60:
drivers/net/wireless/wavelan_cs.h:97:1: warning: "LCSR" redefined
In file included from include/asm/arch/hardware.h:56,
from include/asm/hardware.h:16,
from include/asm/arch/io.h:13,
from include/asm/io.h:71,
from drivers/net/wireless/wavelan_cs.p.h:433,
from drivers/net/wireless/wavelan_cs.c:60:
include/asm/arch/SA-1100.h:1907:1: warning: this is the location of the previous definition
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Adam Brooks
Fixes an issue in 2.6.15-rc2 that prevented compilation of kernels for IOP3xx boards.
Signed-off-by: Adam Brooks <adam.j.brooks@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since the defintion of NODES_SHIFT may be overridden in asm/arch/memory.h
it's important to include asm/memory.h into asm/numnodes.h to ensure
that the correct value is always defined.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Kenneth Tan
To add queue manager region size which is missing from ixp4xx-regs.h
Signed-off-by: Kenneth Tan <chong.yin.tan@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The receiver status register reports latched error conditions, which
must be cleared by writing to it. However, the data register reports
unlatched conditions which are associated with the current character.
Use the data register to interpret error status rather than the RSR.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Unfortunately, later gcc versions error out when our get_user is passed
a const pointer, since we write to a temporary variable declared as
typeof(*(p)) which propagates the const-ness.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The "align" argument in ARMs __ioremap is unused and provides a
misleading expectation that it might do something. It doesn't.
Remove it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In the old days when arm26/arm32 was combined into the same
architecture, proc-fns.h provided the xchg implementation for
arm26 CPUs. Since we no longer combine these two, this include
is no longer required. Remove it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since atomic.h does not include types.h, u32 may not be defined.
Since atomics are supposed to work on unsigned long quantities,
use unsigned long instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Unfortunately, using PAGE_SHIFT in asm/arch/memory.h is unsafe, and we
can't include asm/page.h into this file because then we have a circular
dependency. Move the offending code to arch/arm/common/sa1111.c
instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
atomic.h, bitops.h and mmu_context.h are using likely/unlikely.
thread_info.h uses __attribute_const__. Hence these files require
linux/compiler.h to be included.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Christoph Lameter
Badari Pulavarty
Linus Torvalds
Richard Purdie
Stephen Hemminger
Daniel Jacobowitz
Deepak Saxena
Hiroki Kaminaga
Arthur Othieno
Russell King
Lucas Correia Villa Real
Adam Brooks
Kenneth Tan